+static int get_start_reg_index(ir_graph *irg, const arch_register_t *reg)
+{
+ ir_node *start = get_irg_start(irg);
+ unsigned n_outs = arch_get_irn_n_outs(start);
+ int i;
+
+ /* do a naive linear search... */
+ for (i = 0; i < (int)n_outs; ++i) {
+ const arch_register_req_t *out_req
+ = arch_get_irn_register_req_out(start, i);
+ if (! (out_req->type & arch_register_req_type_limited))
+ continue;
+ if (out_req->cls != arch_register_get_class(reg))
+ continue;
+ if (!rbitset_is_set(out_req->limited, reg->index))
+ continue;
+ return i;
+ }
+ panic("Tried querying undefined register '%s' at Start", reg->name);
+}
+
+ir_node *be_get_initial_reg_value(ir_graph *irg, const arch_register_t *reg)
+{
+ int i = get_start_reg_index(irg, reg);
+ ir_node *start = get_irg_start(irg);
+ ir_mode *mode = arch_register_class_mode(arch_register_get_class(reg));
+ const ir_edge_t *edge;
+
+ foreach_out_edge(start, edge) {
+ ir_node *proj = get_edge_src_irn(edge);
+ if (!is_Proj(proj)) // maybe End/Anchor
+ continue;
+ if (get_Proj_proj(proj) == i) {
+ return proj;
+ }
+ }
+ return new_r_Proj(start, mode, i);
+}
+
+int be_find_return_reg_input(ir_node *ret, const arch_register_t *reg)
+{
+ int arity = get_irn_arity(ret);
+ int i;
+ /* do a naive linear search... */
+ for (i = 0; i < arity; ++i) {
+ const arch_register_req_t *req = arch_get_irn_register_req_in(ret, i);
+ if (! (req->type & arch_register_req_type_limited))
+ continue;
+ if (req->cls != arch_register_get_class(reg))
+ continue;
+ if (!rbitset_is_set(req->limited, reg->index))
+ continue;
+ return i;
+ }
+ panic("Tried querying undefined register '%s' at Return", reg->name);
+}
+